Bioterrorism has not received serious attention until recently. That view has changed, however, since the possibility of a biological weapon being deployed against military or civilian personnel suddenly became a reality. The exposure of up to tens of thousands of people to anthrax spores through the US Postal Service this past autumn sparked this fear, and hence, has generated an urgent need to develop new methods to rapidly respond to the threat of a biological attack. Vaccination is currently believed to offer one of the best solutions for preventing the successful execution of a biological attack. Immunization against biological agents has a history of generally being an effective method of protecting large populations against a wide variety of infectious diseases. However, technologies that enable the rapid development and mass production of new vaccines in response to the threat of bioterrorism are lacking. In response to this challenge, the Company created the VesiVaxr system, which consists of a flexible and easily modified gene cassette designed to rapidly engineer and produce antigen fusion proteins that can easily be formulated in liposomes possessing potent immunostimulatory properties. VesiVaxr vaccines offer a safer and more effective approach to vaccination because they present specific antigens to the immune system without the problems associated with whole pathogen vaccines. The primary objective of this project is to show that the VesiVaxr system can be used to rapidly respond to the threat of a biological attack. For this purpose, the Company has chosen Bacillus anthracis as a model bioterrorism pathogen to demonstrate the utility of VesiVaxr technology. In the Phase I studies, the Company plans to insert several anthrax epitopes into its proprietary gene cassette system (Specific Aim 1), express and purify the anthrax antigen fusion proteins (Specific Aim 2), and then formulate them in liposomes previously determined to have potent immunostimulatory properties (Specific Aim 3). The target antigens that have been selected for insertion into the gene cassette are based upon segments of the Protective Antigen (PA) that have been reported to generate antibodies implicated in providing protection from infection with anthrax. Evaluation of the anthrax antigen liposomes in preclinical animal models will be conducted in the Phase II studies.